Oracle database errors out with the message "You are trying to use the MEMORY_TARGET feature. This feature requires the /dev/shm file system to be mounted", why ?

Issue

• Oracle is configured to use Advanced Memory Management (AMM). When connecting/starting the Oracle database, the following error message is printed :

===========Oracle databse error=====
Starting ORACLE instance (normal)
WARNING: You are trying to use the MEMORY_TARGET feature. This feature requires the /dev/shm file system to be mounted for at least <X> bytes. /dev/shm is either not mounted or is mounted with available space less than this size. Please fix this so that MEMORY_TARGET can work as expected. Current available is <Y> and used is <Z> bytes. Ensure that the mount point is /dev/shm for this directory.
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